New Findings of the Moon Revealed by Chang'e-2 Microwave Radiometer Data

The microwave radiometer (MRM) onboard Chang'e-1/2 satellites has obtained multi-channel brightness temperatures (TBs) covering the entire lunar surface, which is unique to the current lunar remote sensing. The microwave can penetrate the regolith to certain depth, and they are sensitive to the compositions and temperatures in depth layer, making it of great significance in lunar scientific research compared to the commonly used visible, thermal infrared and radar data. Based on MRM data, the main findings include the following three aspects:: (1) After comparing the TB behaviors in the main basaltic units with the visible and radar results, we propose that the MRM data can represent the basaltic units in different episodes. (2) The warm anomaly in microwave range is defined, which reveals the anomalously high thermal flux and even the thermal state of the current lunar crust. (3) The cold anomaly in microwave range is defined, which indicates the existence of the rocks and/or a kind of special material. The latter brings about the considerably low daytime TB and high nighttime TB, potentially indicating the heterogeneity of the lunar crust in vertical direction.